This invention is in the field of electronic measurement. Embodiments are more specifically directed to devices and methods of identifying the type and composition of paper media using a measurement of its impedance.
As known in the art, many different types of paper are available for use in conventional desktop and office printer equipment. Ink-jet printers in particular are called upon to print text and images on a wide variety of paper types ranging from photo paper, to bond paper based on cotton or linen, to paper that is specifically formulated for ink-jet printing, to so-called “plain” paper. For example, photo paper is typically coated with a material that is highly ink-absorbent to provide good color saturation, while preventing wicking of the ink along the fibers of the underlying substrate. Similarly, papers for high quality ink-jet printing will include a similar absorbent coating that prevents wicking or buckling from wetting by large ink loads. Plain paper can support a light link load, but is not suitable for heavier ink usage.
As such, many printers suggest the use of different print settings for the various paper types, in order to attain the highest print quality available for the paper being used. The appropriate setting is typically entered by the user initiating the print task, for example by his selecting of a paper type via a pull-down menu displayed by a computer coupled to the printer. This of course requires attentiveness on the part of the user, as well as knowledge of the type of paper being used as well as the desired print quality. In many cases, it is suspected that the user merely uses the printer default setting, or the last setting entered, in which case the quality of the printed output will be less than optimal if not acceptable, leading to the waste of paper, ink, and time.